Counsel out = polite way of saying you are the weakest link, good byeCompulsory redundancy = nothing personal, but we're getting smaller so don't have enough work for youThere's some overlap, but generally different reasons for using each. CR involves a mandatory payout (albeit small) but can be instituted across an entire group or workforce (in fact, the more blanketed the approach, the better). CO means no payout, but can mean more paperwork and time spent "counselling"/dropping hints to the individual.With regard to underperformers already being counselled out, there are always underperformers - by definition, 50% are performing below average at any given time. As soon as one lot goes, the next-worst performers take their place as the "underperformers".
